include/lttng/trigger/trigger-internal.h

   1 /*
   2  * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #ifndef LTTNG_TRIGGER_INTERNAL_H
   9 #define LTTNG_TRIGGER_INTERNAL_H
  10
  11 #include <lttng/trigger/trigger.h>
  12 #include <common/credentials.h>
  13 #include <common/dynamic-array.h>
  14 #include <common/macros.h>
  15 #include <common/optional.h>
  16 #include <stdint.h>
  17 #include <stdbool.h>
  18 #include <sys/types.h>
  19 #include <urcu/ref.h>
  20
  21 struct lttng_payload;
  22 struct lttng_payload_view;
  23
  24 struct lttng_trigger {
  25         /* Reference counting is only exposed to internal users. */
  26         struct urcu_ref ref;
  27
  28         struct lttng_condition *condition;
  29         struct lttng_action *action;
  30         char *name;
  31         /* For now only the uid portion of the credentials is used. */
  32         struct lttng_credentials creds;
  33         /*
  34          * Internal use only.
  35          * The unique token passed to the tracer to identify an event-rule
  36          * notification.
  37          */
  38         LTTNG_OPTIONAL(uint64_t) tracer_token;
  39 };
  40
  41 struct lttng_triggers {
  42         struct lttng_dynamic_pointer_array array;
  43 };
  44
  45 struct lttng_trigger_comm {
  46         /*
  47          * Credentials, only the uid portion is used for now.
  48          * Used as an override when desired by the root user.
  49          */
  50         uint64_t uid;
  51         /*
  52          * Length of the variable length payload (name, condition, and
  53          * an action).
  54          */
  55         uint32_t length;
  56         /* Includes '\0' terminator. */
  57         uint32_t name_length;
  58         /* A null-terminated name, a condition, and an action follow. */
  59         char payload[];
  60 } LTTNG_PACKED;
  61
  62 struct lttng_triggers_comm {
  63         uint32_t count;
  64         uint32_t length;
  65         /* Count * lttng_trigger_comm structure */
  66         char payload[];
  67 };
  68
  69 LTTNG_HIDDEN
  70 ssize_t lttng_trigger_create_from_payload(struct lttng_payload_view *view,
  71                 struct lttng_trigger **trigger);
  72
  73 LTTNG_HIDDEN
  74 int lttng_trigger_serialize(const struct lttng_trigger *trigger,
  75                 struct lttng_payload *payload);
  76
  77 LTTNG_HIDDEN
  78 bool lttng_trigger_validate(const struct lttng_trigger *trigger);
  79
  80 LTTNG_HIDDEN
  81 int lttng_trigger_assign_name(
  82                 struct lttng_trigger *dst, const struct lttng_trigger *src);
  83
  84 LTTNG_HIDDEN
  85 void lttng_trigger_set_tracer_token(
  86                 struct lttng_trigger *trigger, uint64_t token);
  87
  88 LTTNG_HIDDEN
  89 uint64_t lttng_trigger_get_tracer_token(const struct lttng_trigger *trigger);
  90
  91 LTTNG_HIDDEN
  92 int lttng_trigger_generate_name(struct lttng_trigger *trigger,
  93                 uint64_t unique_id);
  94
  95 LTTNG_HIDDEN
  96 bool lttng_trigger_is_equal(
  97                 const struct lttng_trigger *a, const struct lttng_trigger *b);
  98
  99 LTTNG_HIDDEN
 100 void lttng_trigger_get(struct lttng_trigger *trigger);
 101
 102 LTTNG_HIDDEN
 103 void lttng_trigger_put(struct lttng_trigger *trigger);
 104
 105 /*
 106  * Allocate a new set of triggers.
 107  * The returned object must be freed via lttng_triggers_destroy.
 108  */
 109 LTTNG_HIDDEN
 110 struct lttng_triggers *lttng_triggers_create(void);
 111
 112 /*
 113  * Return the a pointer to a mutable element at index "index" of an
 114  * lttng_triggers set.
 115  *
 116  * This differs from the public `lttng_triggers_get_at_index` in that
 117  * the returned pointer to a mutable trigger.
 118  *
 119  * The ownership of the trigger set element is NOT transfered.
 120  * The returned object can NOT be freed via lttng_trigger_destroy.
 121  */
 122 LTTNG_HIDDEN
 123 struct lttng_trigger *lttng_triggers_borrow_mutable_at_index(
 124                 const struct lttng_triggers *triggers, unsigned int index);
 125
 126 /*
 127  * Add a trigger to the triggers set.
 128  *
 129  * A reference to the added trigger is acquired on behalf of the trigger set
 130  * on success.
 131  */
 132 LTTNG_HIDDEN
 133 int lttng_triggers_add(
 134                 struct lttng_triggers *triggers, struct lttng_trigger *trigger);
 135
 136 /*
 137  * Serialize a trigger set to an lttng_payload object.
 138  * Return LTTNG_OK on success, negative lttng error code on error.
 139  */
 140 LTTNG_HIDDEN
 141 int lttng_triggers_serialize(const struct lttng_triggers *triggers,
 142                 struct lttng_payload *payload);
 143
 144 LTTNG_HIDDEN
 145 ssize_t lttng_triggers_create_from_payload(struct lttng_payload_view *view,
 146                 struct lttng_triggers **triggers);
 147
 148 LTTNG_HIDDEN
 149 const struct lttng_credentials *lttng_trigger_get_credentials(
 150                 const struct lttng_trigger *trigger);
 151
 152 LTTNG_HIDDEN
 153 void lttng_trigger_set_credentials(struct lttng_trigger *trigger,
 154                 const struct lttng_credentials *creds);
 155
 156 /*
 157  * Return the type of any underlying domain restriction. If no particular
 158  * requirement is present, returns LTTNG_DOMAIN_NONE.
 159  */
 160 LTTNG_HIDDEN
 161 enum lttng_domain_type lttng_trigger_get_underlying_domain_type_restriction(
 162                 const struct lttng_trigger *trigger);
 163
 164 /*
 165  * Generate any bytecode related to the trigger.
 166  * On success LTTNG_OK. On error, returns lttng_error code.
 167  */
 168 LTTNG_HIDDEN
 169 enum lttng_error_code lttng_trigger_generate_bytecode(
 170                 struct lttng_trigger *trigger,
 171                 const struct lttng_credentials *creds);
 172
 173 LTTNG_HIDDEN
 174 struct lttng_trigger *lttng_trigger_copy(const struct lttng_trigger *trigger);
 175
 176 /*
 177  * A given trigger needs a tracer notifier if
 178  *  it has an event-rule condition,
 179  *  AND
 180  *  it has one or more sessiond-execution action.
 181  */
 182 LTTNG_HIDDEN
 183 bool lttng_trigger_needs_tracer_notifier(const struct lttng_trigger *trigger);
 184
 185 #endif /* LTTNG_TRIGGER_INTERNAL_H */